Akademik Veri Yönetim Sistemi
2018 MRS Fall Meeting- Boston U.S.A , Massachusetts, Amerika Birleşik Devletleri, 25 - 30 Kasım 2018, ss.896-897
EP08.10.06
Aluminum Nitride Nanowire Flexible Ultraviolet Photodetectors Yassir A. Ali and Kasif Teker; Electrical and Electronics Engineering, Istanbul Sehir
University, Istanbul, Turkey.
One-dimensional nanostructured wide bandgap (WBG, typically[endif]-->between 3 eV – 6 eV) semiconductor materials are good candidates as building
blocks for photosensitive device applications such as UV photodetectors, phototransistors, and photodiodes. Furthermore, high UV light sensitivity, small
size, very short response time, low power consumption, and high efficiency are the most important features of nanodevices for new and superior
applications photonics. AlN nanostructures, an important III-V WBG semiconductor, have aroused significant interest due to its large direct bandgap (6.28
eV), low electron affinity, high thermal conductivity, high melting point (above 2300oC), and chemical stability. Despite its intrinsic superior properties,
challenges in synthesis of defect free and uniform morphology AlN nanostructures persist, thereby limiting the number of electronic and photonic device
studies.
This paper presents the fabrication of a flexible ultraviolet (UV) photodetector from free-standing catalyst-free AlN nanowire (AlNNW) films via a direct
transfer method through a very low-cost non-lithographic fabrication scheme. The device has demonstrated very fast photoresponse rise and decay times of
0.27 s and 0.41 s to the deep-UV light illumination, respectively. The photocurrent measurements have been conducted for bias voltages from 1V to 20V.
In fact, the flexible AlNNW photodetector is very sensitive to the UV illumination even at low bias voltages (as low as 1V) indicating very high sensitivity
and capability of operating at low voltages. Moreover, the photocurrent has decayed to the dark current value rapidly, after the exposure ended, suggesting
the absence of defect-related traps. Consequently, the facile fabrication scheme is very cost-effective, readily scalable; and offers broad integration
capabilities in various flexible photonic and electronic applications including wearable devices.